2000
#7,289
National surname rank
Recorded bearers 4,216
First available Census row
Per 100,000 1.56
Rare Last name
Loos
A Dutch and German toponymic surname indicating an origin near a marsh, bog, or wetland.
According to the 2020 US Census Bureau surname tables, roughly 4,510 Americans carry the last name Loos. That puts it at #8,071 in the national surname ranking, appearing at a frequency of 1.32 per 100,000 people (about 1 in 75,999 residents).
This page is the full Name Census profile for the Loos surname. You will find the Census Bureau frequency data, a multi-census history view, an ancestry and ethnicity breakdown based on self-reported demographics, the name's meaning and origin where available, and answers to the most common questions people ask about this surname.
Bearers in the US
4.5K
1 in 75,999
Census rank
#8,071
2020 decennial data
Per 100,000
1.3
Frequency rate
Recorded bearers
3.9K
rare in the US
Popularity narrative
The Census Bureau recorded 3,933 bearers of the surname Loos in its 2020 decennial surname file. At a rate of 1.32 per 100,000 residents, it holds the 8071st position in the national surname ranking.
Among Census respondents with the surname Loos, the largest self-reported group is White at 92.5%. The next largest groups are Two or More Races (3.3%) and Hispanic (2.4%).
Origin
Meaning and origin of Loos
The surname Loos is of Dutch origin, with roots dating back to the Middle Ages. It is derived from the Dutch word 'loos,' which means 'cunning' or 'sly.' The name likely originated as a nickname for someone perceived as crafty or shrewd.
The earliest recorded instances of the Loos surname can be found in various Dutch historical records from the 13th and 14th centuries. One notable example is the mention of a Wouter Loos in a 1328 document from the city of Leiden. The name also appeared in various medieval manuscripts and records from other Dutch cities like Amsterdam and Rotterdam.
In the 15th century, the Loos surname started to spread beyond the Netherlands. It can be found in historical records from neighboring regions like Belgium and parts of northern Germany. This was likely due to migration and trade routes connecting these areas.
The Loos surname has been associated with several notable individuals throughout history. One of the earliest was Pieter Loos (c. 1550-1621), a renowned Dutch painter and etcher from Amsterdam. Another was Adriaen Loos (1615-1670), a Dutch Golden Age painter known for his portraits and genre scenes.
During the 17th and 18th centuries, the Loos name gained prominence in various fields. Hans van Loos (1631-1686) was a Dutch Golden Age painter and art dealer. Johann Loos (1672-1738) was a German architect who worked in Russia and designed several notable buildings in St. Petersburg.
In the 19th century, Adolf Loos (1870-1933) was an influential Austrian architect and key figure in the modern architecture movement. He is known for his influential essay "Ornament and Crime," which criticized excessive ornamentation in architecture.
Other notable individuals with the Loos surname include Jacques Loos (1924-2019), a French resistance fighter during World War II, and Walter Loos (1913-1986), a German actor and director best known for his work in the theater.
While the Loos surname originated in the Netherlands, it has since spread to various parts of the world, including North America, where it was brought by Dutch and German immigrants in the 17th and 18th centuries.
Demographics
Ancestry and ethnicity for Loos
Among Census respondents with the surname Loos, the largest self-reported group is White at 92.5%. The next largest groups are Two or More Races (3.3%) and Hispanic (2.4%).
The bar chart below shows how Loos bearers described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given surname, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown for every Census year so the breakdown stays comparable over time. When the source file also includes raw headcounts, Name Census shows those alongside the percentages in the legend.
Keep in mind that these are self-reported numbers. A person's surname does not determine their race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the Loos surname at the time of the 2020 Census, not any inherent property of the name itself.
- White92.5% · 3,637
- Two or more races3.3% · 129
- Hispanic or Latino2.4% · 94
- Asian and Pacific Islander1.4% · 56
- Black or African American0.4% · 15
- American Indian and Alaska Native0.1% · 2
Timeline
Historical Census data for Loos
Loos appears in 3 published Census surname files: 2000, 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2010
#8,159
National surname rank
Recorded bearers 4,064
-152 bearers (-3.6%)
Per 100,000 1.38
Rank movement Down 870 places
2020
#8,071
National surname rank
Recorded bearers 3,933
-131 bearers (-3.2%)
Per 100,000 1.32
Rank movement Up 88 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #7,289 | 4,216 | 1.56 | First available Census row | First available Census row |
| 2010 | #8,159 | 4,064 | 1.38 | -152 bearers (-3.6%) | Down 870 places |
| 2020 | #8,071 | 3,933 | 1.32 | -131 bearers (-3.2%) | Up 88 places |
For 2020, the Census Bureau published race and Hispanic-origin columns as counts rather than percentages. Name Census converts those counts back into shares so the ancestry section stays comparable with the older surname files.
Year on year
2010 vs 2020 Census
How has the Loos surname changed between Census years? The chart shows bearer count side by side, and the table compares rank, count, and frequency.
Census year comparison
20102020
| Metric | 2010 | 2020 | Change |
|---|---|---|---|
| Rank | #8,159 | #8,071 | 1.1% |
| Count | 4,064 | 3,933 | -3.2% |
| Per 100K | 1.38 | 1.32 | -4.6% |
Between the 2010 and 2020 Census, the number of Loos bearers went from 4,064 to 3,933 (-3.2% change). The surname moved up 88 positions in the national ranking, going from #8,159 to #8,071.
FAQ
Loos surname: questions and answers
How many people in the U.S. have the surname Loos?
Name Census estimates that about 4,510 living Americans carry the surname Loos. Using the current population baseline, that works out to roughly 1 in 75,999 residents.
How common is Loos?
Loos ranks #8,071 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 1.32 per 100,000 residents, which is about 1 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 3,933 people with the surname Loos. That is different from the site's living-bearer estimate (4,510), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 1.32 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 1.32 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 1 of them to have the surname Loos.
Has Loos become more or less common over time?
Between 2010 and 2020, the surname Loos went from 4,064 recorded bearers to 3,933. That is a decrease of 131 (-3.2%). In the national ranking it rose from #8,159 to #8,071.
What does the Census say about the background of Loos?
Among Census respondents with the surname Loos, the largest self-reported group is White at 92.5%. The next largest groups are Two or More Races (3.3%) and Hispanic (2.4%). These figures come from the 2020 Census Bureau surname tables, based on how respondents described their own race and ethnicity.
Which group reports this surname most often?
White is the largest self-reported group for the surname Loos in the 2020 Census, accounting for 92.5% (3,637 people in the source table).
What is the full ancestry breakdown?
Loos appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (92.5%), Two or More Races (3.3%), Hispanic (2.4%). For 2020, the source file also published raw headcounts for each group, which is why this page can show both percentages and counts in the ancestry section.
Is this page using the latest Census data?
Yes. This page is using the latest surname file currently loaded on Name Census, which is 2020. The historical section above also keeps any older Census surname entries we have for Loos (2000, 2010, 2020).
Does the Census include every surname?
No. The Census Bureau only publishes surnames that appeared at least 100 times in a given decennial Census. That means very rare surnames are excluded entirely, and a surname can appear in one Census release but disappear from a later one if it falls below the reporting threshold.
Why don't the ancestry percentages always add up to exactly 100%?
There are two main reasons: rounding and suppression. The Census Bureau rounds published values, and it may suppress very small cells to protect privacy. For 2020, the Bureau also published raw group counts rather than direct percentages, so Name Census converts those counts back into shares for comparability across census years.
What does Loos mean?
A Dutch and German toponymic surname indicating an origin near a marsh, bog, or wetland. The fuller origin note on this page goes into more detail.
Where does the surname data come from?
All surname statistics on Name Census are drawn from the US Census Bureau's decennial surname frequency tables. These files list every surname that appeared 100 or more times in the 2020 Census, along with a count, a per-100,000 rate, and a self-reported demographic breakdown. You can read the full explanation on our methodology page.
How does Name Census estimate living bearers?
For surnames, Name Census does not age cohorts the way it does for first names. Instead, it takes the Census Bureau's published frequency for Loos (1.32 per 100,000) and applies that rate to the current U.S. resident population to estimate how many living Americans have the surname today.
How common is the surname Loos?
For a quick modern take, check how many Americans have the surname Loos on our sister site HowManyOfMe.org.